Senior Network Engineer

Network Engineer - £450 - £500 Per Day (Outside IR35) – 3 Months Rolling – London (Hybrid)

Overview

We are currently partnered with a leading UK enterprise seeking an experienced Network Engineer to join a major data centre migration and network transformation programme on an initial 3-month rolling contract in London.

The successful candidate will be responsible for designing, implementing and migrating complex enterprise network infrastructure, with a particular focus on Cisco ACI, Fortinet Firewalls and F5 Load Balancers. This is a hands-on, project-focused opportunity involving large-scale data centre migrations, network modernisation and secure connectivity across hybrid infrastructure environments, with no BAU support responsibilities.

Role & Responsibilities

• Design, implement and migrate enterprise network infrastructure across complex data centre environments.
• Lead technical delivery of data centre migration activities, ensuring minimal disruption to business-critical services.
• Configure, deploy and troubleshoot Cisco ACI fabrics, including network policies, endpoint groups and connectivity.
• Implement and manage Fortinet FortiGate firewalls, including firewall policies, routing, NAT and VPN configurations.
• Configure and migrate F5 LTM load balancing solutions, ensuring application availability and performance.
• Produce High-Level and Low-Level Designs (HLDs/LLDs), network diagrams and technical documentation.
• Plan and execute network migration activities, including cutovers, testing, validation and rollback procedures.
• Implement routing, switching, network segmentation and secure connectivity across data centre infrastructure.
• Collaborate with infrastructure, cloud, security and application teams to manage dependencies throughout migration activities.
• Troubleshoot complex network issues across Cisco ACI, Fortinet and F5 environments during implementation and migration.
• Develop migration runbooks, implementation plans and technical handover documentation.

Essential Skills & Experience

• Proven experience delivering large-scale data centre migrations and enterprise network transformation projects.
• Strong hands-on Cisco ACI experience, including fabric configuration, policy management, EPGs and troubleshooting.
• Strong Fortinet FortiGate experience, including firewall configuration, security policies, routing, NAT and VPNs.
• Hands-on F5 LTM experience, including load balancing, virtual servers, pools and application traffic management.
• Strong understanding of data centre network architecture, connectivity and infrastructure migration methodologies.
• Excellent knowledge of routing and switching technologies including BGP, OSPF, VLANs, NAT and IPSec VPNs.
• Experience planning and executing complex network cutovers, migrations and rollback procedures.
• Proven ability to troubleshoot complex connectivity, firewall and application delivery issues.
• Experience working across hybrid cloud and on-premise enterprise infrastructure environments.
• Familiarity with network automation technologies including Python, Terraform and/or Ansible would be advantageous.
• Excellent technical documentation and stakeholder communication skills, with the ability to operate in fast-paced project environments.

Package & Location

• Day Rate: £450 - £500 Per Day (Outside IR35)
• Contract Length: 3 Months (Rolling Contract)
• Location: London (Hybrid)

Network Engineer - £450 - £500 Per Day (Outside IR35) – 3 Months Rolling – London (Hybrid)